1. Field of the Invention
The present invention relates to a two-part mailer incorporating a conventional return envelope and a method of assembling it.
2. Description of the Related Art
Continuously fed laser printers using heat and pressure to fuse imaged data onto a web part processed through them cannot accept web parts with heat-sensitive glue. However, a mailing product, i.e. a so-called "mailer", can be assembled by manufacturing multiple separate web parts, one of which contains no adhesive or die-cut window/patch, processing this one web through a heat-fusion printer, collating this one web to another web which is manufactured with a heat-sensitive adhesive on all edges and which contains one or more die-cut windows or patches, detaching each web part from a continuous line of web parts which are all joined together lengthwise edge to lengthwise edge, and finally sealing the detached multiple web parts to each other.
This prior art method of assembly is applicable for those mailers not requiring a remittance via a return envelope. However, for a two-way communication requiring the remittance of a payment or the like, it is desirable to incorporate a return envelope into the mailer. Heretofore, a multiple part mailer incorporating a return envelope has not been manufactured using web parts which are processed through continuously fed laser printers because the glue used to create the multi-part mailer melts and also because the bulk of the multi-part mailer with a return envelope incorporated therein has prevented their passage through conventional laser printers.
Consequently, prior art multi-part mailers incorporate return envelopes by being manufactured with at least three and sometimes four parts which are then collated together to form the return envelope inside the mailer. This prior art method of assembly has created several concerns for manufacturers.
First, a separate press run is required to print on one side of the return envelope which is usually made of two web parts itself.
Second, an additional pass through the hot-melt glue applicator is required to apply the adhesive to the return envelope of the multi-part mailer.
Third, a collator pass is required to paste these web parts together so that the return envelope may be secured inside the multi-part mailer.
Fourth, perforations which are required for opening the multi-part mailer must be extremely exact since at least three web parts, before being sealed together, are to be perforated. With a return envelope incorporated between the end web parts, exact alignment of the perforations is extremely difficult to achieve.
Fifth, matching of perforations along all web parts to be joined together is more difficult to achieve whenever the method of assembly is performed at the site of the customer's business because some degree of quality control is lost by the manufacturer of the assembling equipment.
Sixth, opening of the multi-part mailer incorporating a return envelope as two parts thereof is sometimes difficult for the recipient of the mailer if alignment of the perforations between the various web parts has not been accurately made.
Among prior art patents, the affixing of envelopes onto continuous carriers is known for various purposes from Cone, U.S. Pat. No. 4,091,987; Gendron, U.S. Pat. No. 3,912,160; Sebring, U.S. Pat. No. 3,554,447; and Porter, U.S. Pat. No. 3,273,784. It is also known to enclose an envelope in a mailer with the envelope more or less filling the entire outgoing mailer. See Dicker, U.S. Pat. No. 4,157,759. Neubauer teaches in U.S. Pat. No. 4,361,269 that the plies of a Dicker-type mailer may be secured together by hot-melt, pressure-sensitive adhesive. A process for the production of mailable business letters is disclosed by Heinrich in West German Pat. No. 29 00 226 in which two webs are shown, one carrying a glue pattern.
However, none of these references solve all of the problems either existing in conventional mailers with envelopes inside or known to exist in prior art methods of assembling mailers having usually four web parts.